Looking at the effect of providing high-quality preschool to children of impoverished families, the authors found that full-time, high-quality pre-school for children under the age of 3 could entirely eliminate the achievement gap between children from low-income familes and those from high-income families.

More important, the authors found that the impact of quality pre-school continued even if the children did not stay in quality care after age 3. At 5, about three-fourths of the gap remains closed. Entering kindergarten, there is little difference between low-income kids and kids from higher-income families. Even at age 8, five years after the program ended, some three-fifths of the IQ and math achievement gap remained closed. And the impact appears to continue for most children through age 18.

“Whatever happens during those first three years has an outsized impact,” said Sojourner. “So if you want to raise adult productivity, spend your next dollar there, in these early years.”

Although the cost of universal preschool may seem expensive, the results are more than worth it according to Sojourner. Indeed, another study by economist Art Rolnick and Rob Grunewald showed that the return on the public’s investment in preschool for low-income children was more than $16 for every dollar spent. Referring to Sojourner’s study, Rolnick said, “There is an overwhelming amount of evidence that is now building through Aaron’s work in particular to show that indeed we can expect a very, very high return to the public by investing in high quality early education for our children.”

The results of quality pre-school for impoverished children could have far-reaching impacts on our nation.

Not only could it help diminish the growing income divide between the rich and the poor (85 people now own more wealth than 3.5 billion people – more than all of Asia). It could help revitalize our shrinking middle class and the American dream. (Of all the advanced nations, the US has the least upward mobility. As a result, 42 percent of Americans born into poverty will not get out.)

Universal preschool could help lower our enormous prison population (the US has 5 percent of the world’s population and 25 percent of the world’s prisoners), since there is a direct link between those who lack education and those who wind up in prison. It could also help cut social programs, such as food stamps and other anti-poverty safety nets. It could help diminish the racial divides associated with poverty. It could improve our economy through increased productivity and increased tax revenues. And, combined with low-cost universal childcare, it could narrow the gender pay gap by enabling more women to hold full-time jobs. (For example, after Quebec instituted a low-cost universal childcare program, so many women entered the workforce the program more than paid for itself in tax revenues.)

Perhaps a statement by Nobel prize-winning economist, James Heckman, sums up the issue best. He said, “Universal preschool is not socialism. It’s fixing a market failure. We’re saving money for everyone, including the taxpaying middle class and upper class. Right now they’re supporting prisons, health, special education in schools. The benefit is broadly shared. … It’s something that would actually accrue to the whole country.”

Given all of the potential benefits, is it any wonder that President Obama called for universal pre-kindergarten programs during his 2013 State of the Union address?